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information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Response to SCA-TR-2017-SEC008, 

“Draft Review of Internal Alpha Exposure 

Potential at CPP Prior to 1963” 

Response Paper

National Institute for Occupational 

Safety and Health

April 18, 2018 

W. M. Findley

Oak Ridge Associated Universities Team

Reviewed by T. D. Taulbee 

Division of Compensation Analysis and Support
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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TABLE OF CONTENTS

Abbreviations and Acronyms ..........................................................................................................3

Summary Response to Findings.......................................................................................................4

Responses to Separate Findings .......................................................................................................6

Responses to Separate Observations ..............................................................................................32

References ......................................................................................................................................34
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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ABBREVIATIONS AND ACRONYMS

α alpha 

ABRWH Advisory Board on Radiation and Worker Health

AEC Atomic Energy Commission, a predecessor of the United States Department of 

Energy

β beta 

CAMS continuous air monitors

cpm counts per minute; may also be denoted as c/m

CPP Chemical Processing Plant

DCAS NIOSH Division of Compensation Analysis and Support

DOE Department of Energy

dpm disintegrations per minute; may also be denoted as d/m

ER evaluation report

FAP fission and activation products

HEU highly enriched uranium

HP health physics

HSL Health Services Laboratory, a predecessor name for the Radiological and 

Sciences Laboratory (RESL)

INL Idaho National Laboratory

MPC maximum permissible concentration

NIOSH National Institute for Occupational Safety and Health

ORAUT Oak Ridge Associated Universities Team

Pu plutonium

RCG radiological control guidelines

SC&A Sanford Cohen and Associates

SEC Special Exposure Cohort

SRDB Site Research Database

SWP safe work permit

TIMS Thermal Ionization Mass Spectrometry

U uranium

UO3 uranium oxide

Y-12 DOE facility in Oak Ridge, Tennessee
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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SUMMARY RESPONSE TO FINDINGS

On July 10, 2017, SC&A released report SCA-TR-2017-SEC008, Revision 0, entitled Draft 

Review of Internal Alpha Exposure Potential at CPP Prior to 1963. The report provides the 

findings and observations from an Advisory Board on Radiation Worker and Health (ABRWH) 

request to evaluate the feasibility of dose reconstruction for workers at the Idaho National 

Laboratory’s (INL) Chemical Processing Plant (CPP) prior to 1963. The recommended start date 

for the proposed class to be added to the Special Exposure Cohort (SEC) for CPP from the 

evaluation of SEC Petition 00219 is 1963. (NIOSH 2017) The SC&A report focused solely on 

the internal exposure potential to alpha-emitting radionuclides, which was the basis for the 

recommended addition to the SEC. 

There were five findings and five observations presented in the Executive Summary section of 

Draft Review of Internal Alpha Exposure Potential at CPP Prior to 1963. Each finding is 

provided below in italic text with a summary response from DCAS provided after each finding. 

Supporting detail is provided in subsequent sections of this report to present the technical bases

for the DCAS responses to the findings. The five observations and DCAS responses are 

presented in a separate section. 

Finding 1: SC&A found multiple examples in sampled Health Physics (HP) logbooks that 

indicate alpha contamination was detected without corresponding indications that beta/gamma 

contamination was also present. This is indicative that there were certain situations and 

locations at CPP in which alpha contamination may have existed that was not comingled with 

FAP material. 

Finding 1 Response Summary: DCAS has concluded that alpha contamination without fission 

products was limited to certain locations within CPP pre-1963 and was related to process stream 

sampling and analyses, as well as final product storage. These locations were known to CPP 

staff. Documented communications with former CPP staff have indicated that contamination, 

with alpha contamination in particular, in CPP, was not tolerated, and was cleaned up quickly 

during its early years. The alpha contamination levels were typically very small and a special 

bioassay program was implemented if an internal exposure to an alpha-emitting radionuclide was 

deemed possible. It should also be recognized that workers involved in end-product activities 

where mixed fission products were not present were placed on a joint “gross beta” bioassay plus 

uranium bioassay program. 

Finding 2: SC&A found examples of alpha monitoring taking place in the Product Bottle Room, 

including smear surveys of product bottles and bird cages, as well as air monitoring for alpha. 

This is evidence that alpha contamination, including airborne contamination, was of concern to 

the HP staff for this area. Given the nature of routine work activities encountered in the Product 

Bottle Room, it is unlikely that workers in this area would also encounter FAP that are 

comingled with the enriched uranium. 
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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Finding 2 Response Summary: The Product Bottle Room was a storage room where filled

stainless steel product bottles containing highly concentrated uranium solutions (the “product”) 

were kept prior to shipment to Oak Ridge, where it was refined and manufactured into reactor 

fuel. The product bottles were stored in containers that looked like “bird cages.” The purpose of 

the “bird cages” was to ensure a safe geometry of the highly enriched uranium (HEU) material 

during storage and movement. Radiological surveillance in the Product Bottle Room was 

performed because HEU was the potential source term for internal exposure, and, as such, 

required monitoring for alpha contamination. Smear surveys of the storage bottles and bird cages 

demonstrate that the CPP Health Physics group was attentive in monitoring those surfaces which 

would most likely become contaminated, in case one of the product bottles leaked, or had, in 

some way, been contaminated externally. DCAS has concluded there is no compelling data to 

indicate that internal exposure potential was even remotely likely.

Finding 3: SC&A identified several area contamination survey maps from 1954, 1955, 1957, 

1960, and 1961 that indicate that alpha contamination may have been the primary radiological 

concern for certain locations at the time of the survey. In many cases, the survey is a general 

contamination survey that did not detect beta/gamma activity, but directed that the identified 

locations with alpha contamination be cleaned up. 

Finding 3 Response Summary: As with the conclusion to Finding #1, DCAS has concluded 

that alpha contamination without fission products was relegated to certain locations within CPP 

pre-1963, and was related to process stream sampling and analyses, as well as final product 

storage. While certain contamination surveys did not report beta/gamma activity, there were 

often separate beta/gamma and alpha contamination surveys performed in the analytical 

laboratories. In the response to Finding 3, it is also pointed out that there was a focus on only 

alpha contamination surveys at CPP during the later data capture trips, in support of the SEC 

Petition 00219 evaluation report. This was due to a focus on alpha contamination surveys in 

determination of a start date for the recommended SEC class. Within the complete survey 

records, there were many more beta-gamma surveys than alpha only surveys.

Finding 4: Based on a limited set of air samples in Room 216 from November of 1954, it is 

apparent that there was airborne alpha activity present. Evidence suggests the airborne alpha 

activity was uranium-233 (U-233) in the form of uranium oxide (U3O8). In two of the three 

examples, the airborne long-lived alpha activity bounded the airborne beta activity. 

Finding 4 Response Summary: DCAS has concluded that U-233 internal exposure potential is 

limited to a very small number of workers, with bioassay monitoring performed as deemed 

necessary. U-233 was an analytical tracer used for Thermal Ionization Mass Spectrometry 

(TIMS) measurements for uranium concentration. The tracer typically contained more activity 

than the sample to be analyzed, and was a known concern for contamination potential by the 

CPP Health Physics staff and analytical laboratory personnel. Bioassay records indicate there 

was special bioassay monitoring performed for U-233. 
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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Finding 5: SC&A identified a single example in which internal monitoring for uranium 

(specifically U-233) occurred out of the 32 reviewed claims who held job titles with the potential 

for laboratory work at CPP. Two samples were provided in the claimant’s monitoring record; 

however, a log of all medical treatment indicates that two additional follow-up samples 

occurred, which are missing from the dosimetry records supplied by the U.S. Department of 

Energy. One of the two follow-up samples was located via the NIOSH process known as “optical 

recognition imaging.” The disposition and availability of the other sample is unknown. 

Finding 5 Response Summary: DCAS has also concluded that the U-233 bioassay records for 

Claim [redacted] appear to be incomplete, based on a Health Record card in the Department of 

Energy (DOE) Response File. The records for Claim [redacted] have been re-requested to 

ascertain if the records may now be available as medical records are now included in DOE 

Response Files from INL. 

In summary, based on further evaluation of the findings and observations from Draft Review of 

Internal Alpha Exposure Potential at CPP Prior to 1963, DCAS still believes it can reconstruct 

doses with sufficient accuracy for workers at CPP before 1963. This conclusion was largely 

reached due to the comprehensive Health Physics at CPP, which included tight contamination 

controls, airborne radioactivity monitoring, attention to changes in source term based on process 

knowledge with appropriate monitoring, and a large in-vitro bioassay program. There was a 

small subset of the CPP workforce that was on a routine uranium bioassay program due to 

internal exposure potential to uranium without fission products present. Internal monitoring for 

most of the CPP workforce for alpha-emitting material was limited, as such monitoring was 

typically incident-based, as the actual exposure potential was likely restricted to certain 

operations and analytical laboratory personnel. Special bioassay monitoring was identified in 

interviews with former CPP workers, as well as in bioassay records and incident reports. 

RESPONSES TO SEPARATE FINDINGS

Finding 1: SC&A found multiple examples in sampled Health Physics (HP) logbooks that 

indicate alpha contamination was detected without corresponding indications that beta/gamma 

contamination was also present. This is indicative that there were certain situations and 

locations at CPP in which alpha contamination may have existed that was not comingled with 

FAP material. 

Finding 1 Response: CPP was a multipurpose plant designed specifically to recover uranium 

from a wide variety of highly-enriched uranium spent nuclear reactor fuels (20 to 93% U-235). 

Fuel reprocessing operations, isotope recovery, and waste calcination were the three major 

processes at CPP. The common health physics practice for controlling internal exposures to 

personnel in most of the facility during its early years was to control the quantity of beta/gamma

contamination, as it was present in much higher quantities than alpha contamination. This has 

been documented in personnel communications in which CPP health physicists indicate that 

contamination in the early years was typically well tagged with fission products. (DCAS 2014a) 
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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However, there were certain known locations within CPP where this relationship did not hold 

true. (DCAS 2016) In the process of recovering highly enriched uranium, most fission products 

were removed from the process stream in the first-cycle extraction raffinate. Sampling of the 

process stream after first cycle, with subsequent analyses in the CPP analytical laboratories, and 

end-product activities such as final recovery of uranium, were known to be alpha contamination 

concerns and were monitored as such. Contamination incidents and contamination measurements 

of note were recorded in HP Logs, with particular attention paid to alpha contamination. 

Significant events would also have a related INL incident report. For context, even lost film 

badges had an incident report. (DCAS 2014b) 

Figure 1 in SCA-TR-2017-SEC008 was provided as an example of alpha contamination at CPP. 

The figure is a screenshot of a Health Physics Daily Logsheet indicating alpha contamination on 

the floor and wall of Room 207 from January, 10 1955 (not 1995). There are ten locations which 

are listed as having been surveyed. The locations listed are Access Corridor (twice), 206, 201, 

Men’s Locker Room, Cell X, 207 (four times) and Front Gate. All alpha contamination 

indications (no contamination levels provided) were from Lab 207, an analytical laboratory. 

Additionally, Figure 2 provides an example from a 1954 CPP Health Physics Log where U-233 

contamination was discovered in Lab 32. No contamination levels were provided except 

“smeared on tops of various equipment pieces; max of 27 c/m on top of south locker.” In both 

cases, the alpha contamination was found in an analytical laboratory, which was the most 

common location for alpha contamination at CPP. [NOTE: U-233 contamination is specifically 

addressed in the response to Finding #4.] 

Table 1 in SCA-TR-2017-SEC008 provides a listing of alpha contamination that was identified 

from a review of CPP Health Physics Logbooks from 1953, 1954, and 1955. The listing provides 

the generic remarks and explanations from the logbooks, with most of the specified areas listed 

as laboratory areas. There are no specific contamination levels provided in Table 1. Table 2 

provides more detailed entries from the Health Physics Logbooks from January and February 

1954. In the seven examples provided, there are four entries which provide contamination levels. 

All are related to laboratory or final product areas. They are: 

• LB-12: up to 100 c/m alpha

• PM Area: up to 35 c/m alpha

• LB Area: up to 250 c/m alpha

• LB-28A: 2 c/m alpha max found

Figures 1, 2 and 3 of this report provide examples of CPP radiological surveys from 1957, 1960, 

and 1962. These surveys include alpha contamination survey data with detected contamination 

reported in cpm. Figures 1 and 2 are from CPP analytical laboratories, while Figure 3 was a 

former analytical laboratory which was modified into a research laboratory. The emphasis on 

alpha contamination due to the nature of the material handled in the laboratory is clear from the 

surveys. Additional examples are provided in the response to Finding #3. The highest potential 

for internal alpha exposure was 3rd cycle extraction and subsequent analytical measurements. 

(DCAS 2014c) It is worth mentioning that the neptunium and plutonium recovery projects, 
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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which involved resubmission of first-cycle raffinate through the first-cycle extraction process 

again to extract these elements, did not take place until 1965, and thus, post-date the time period 

of this review.

Figure 1: Contamination Survey of CPP Lab 207 in March 1957. (CPP 1957, page 6)
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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Figure 2: Contamination Survey of CPP Shift Control Lab in December 1960.

(CPP 1960a, page 4)
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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ABRWH (or their technical support and review contractors) positions unless specifically marked as such. This document represents preliminary 

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Figure 3: Contamination Survey of CPP X Cell in March 1962. (CPP 1962a, page 16)

In the alpha contamination examples provided in SCA-TR-2017-SEC008, and in Figures 1 

through 3 above, a number of observations can be made. First, alpha contamination without 

mixed fission products was limited to the areas and activities associated with final product 

sampling, final product analysis, and final product storage. It was not a facility-wide concern. 

Second, the alpha contamination levels reported are very small. Despite these small quantities, 

the CPP Health Physics staff was diligent in performing alpha contamination surveys and 

providing instructions to clean up any contamination that was detected. These cleanup 

nstructions are often noted on the contamination surveys themselves. Third, alpha contamination 

was not tolerated and was tightly controlled. In the SEC Petition 00219 evaluation report, it was 

determined that it was the increase in alpha contamination levels, along with a general 

acceptance of these contamination levels without additional personnel monitoring, that provided 

the principal reason for recommending CPP for inclusion in the SEC, beginning in 1963. 

While alpha contamination without fission products was likely in certain areas of CPP, it is 

important to remember that a large routine bioassay program was in place at CPP for workers 

with a reasonable potential for internal exposures. CPP did not routinely collect bioassay 
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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samples for uranium, except in cases where workers were determined to have an elevated 

potential for uranium exposure. This can be seen in the CPP Body Fluid Sampling Schedule for 

1956. (Hayden 1956) A complete list of CPP workers participating in the routine bioassay 

program at CPP was provided to the Health Services Laboratory (HSL) which included name, 

department, film badge number, analysis type, and analysis frequency. Even those not required 

to participate in a routine bioassay program, mostly Atomic Energy Commission (AEC) and 

Security personnel, were included in the listing. The most common bioassay method employed at 

CPP was a gross beta urine bioassay, which was adequate for most workers because of the 

presence of mixed fission products in the source term for most of CPP. However, there were 

some workers on a gross beta plus uranium bioassay program. This combination was utilized for 

workers whose work activities placed them in areas where the mixed fission products had been 

removed during the chemical separation process in preparation of the final HEU product. It 

should be noted that any measured activity using a “gross” method resulted in further analysis by 

HSL to determine the radionuclide(s) detected. A breakdown of the number of workers for each 

analysis type and frequency in 1956 is provided in Table 1. 

Table 1: Number of workers on each type of urine bioassay program at CPP in 1956.

(Hayden 1956) 

β (annual) β (semi-annual) β (quarter)

β + U 

(semi-annual or 

quarter)

None

64 50 171 8 19

The bioassay frequency demonstrates that monitoring was focused on workers with the highest 

potential for intake of radioactive material. For example, an annual frequency was typical of 

workers in the Engineering and Operations Evaluation departments, while a quarterly frequency 

was utilized for workers in the Health Physics, Operations, Chemical, and Instrumentation 

department personnel. It is telling that there was a small subset of workers that were placed on a 

gross beta plus uranium routine bioassay program. All of the workers placed on these programs 

were in either the Operations or Chemical departments, and were likely those most involved in 

final product sample collection, analysis, and storage. 

The routine bioassay program at CPP was not a static program. At the discretion of the health 

physicist, the sampling frequency could be changed, based on a perceived risk of uptake 

potential. This was demonstrated in the early 1960s, when monthly 24-hour urine samples were 

collected from personnel who frequented the X-Cell in CPP (an X-Cell contamination survey is 

provided in Figure 3). The X-cell was originally the high level radio-analytical control laboratory 

for CPP, where high activity radioactive samples from the process were analyzed for plant 

control data until 1956. It was repurposed and converted into a research laboratory after the 

Remote Analytical Facilities (CPP-627) was built. The hazards associated with the X-Cell 

correlated with the material and work done in the cell. Gram quantities of alpha emitting 

radionuclides and pure fission product isotopes were handled in the hood, cave, and/or glove 

boxes of the X-Cell, depending on the amounts, concentrations and chemical composition of the 
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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materials. Constant health physics coverage was provided 1) during any particularly hazardous 

work or 2) any time lab personnel requested it. 

The required urine samples were routinely processed for gamma, plutonium, and other 

radionuclides, as needed. Any radioactivity detected by gross analysis was identified, and 

additional samples were requested when it was thought to be necessary. (Stroschein 1967) The 

group of personnel sampled was relatively small, as highly-skilled chemists were needed to 

perform the research in the X-Cell. A review of the in-vitro bioassay data currently being 

assembled for INL coworker models reflected the described increased bioassay monitoring for 

the X-Cell chemists, as is presented in Table 2. This data clearly demonstrates that the increased 

internal exposure potential due to the work in the X-Cell was recognized by the CPP Health 

Physics staff. The stringent bioassay program established reflects the elevated hazard concern. 

Table 2: Example of Enhanced Routine Bioassay Program for X-Cell workers. Data is for 1962-1965.

(INL Coworker In-Vitro Working Dataset)

Job Title Gamma Analyses Plutonium Analyses Strontium Analyses

Chemist 28 32 2 

Chemist 37 41 2 

Chemist 24 24 2 

Analytical Supervisor 11 2 3 

Chemist 27 14 2 

The same philosophy used to determine analyses and frequency for in-vitro bioassay was utilized 

when the in-vivo bioassay program was implemented in 1961. Workers with the highest internal 

exposure potential were counted more frequently. While not a uranium bioassay method, it again 

demonstrates focusing bioassay measurements based on internal exposure potential. An excerpt 

from the 1963 Whole Body Count Frequency Schedule for INL is shown in Figure 4. (McCaslin 

1963) 
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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Figure 4: CPP Whole Body Counting Frequency Schedule for 1963 

(McCaslin 1963) 

Special bioassay was also utilized at CPP. Internal exposure to uranium was carefully controlled 

by the use of Safe Work Permits (SWPs) and monitored via radiation/contamination surveys, as 

well as the use of CAMs (continuous air monitoring) for alpha and beta-emitting radionuclides in 

the ambient air. At CPP pre-1963, special bioassays were conducted for suspected intakes, based 

on radiological indicators and the professional judgement of the CPP Health Physics staff (there 

was at least one HP [Masters-level] and 2-3 technicians [Bachelors-level] on every shift). 

Workers were sent to HSL for bioassay if they had “any facial contamination or if they worked 

in an area where airborne contamination was detected. When alpha contamination was 

discovered in the lab (1950s), the entire crew was sent for urine bioassay – looking for U and Pu. 

Alpha bioassay was done when conditions indicated; alpha contamination was not seen often.” 

(DCAS 2014c) 
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Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

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DCAS has concluded that alpha contamination without fission products was only in certain 

locations within CPP pre-1963 and was related to process stream sampling and analyses. These 

locations were known to the CPP staff. Documented communications with former CPP staff have 

indicated that contamination, with alpha contamination in particular, in CPP was not tolerated 

and was cleaned up quickly. The alpha contamination levels were typically very small, and a 

special bioassay program was implemented if an internal exposure to an alpha-emitting 

radionuclide was deemed possible. It should also be recognized that there was a comprehensive 

bioassay program that included uranium analyses for workers with elevated internal exposure 

potential to the HEU final product. 

Finding 2: SC&A found examples of alpha monitoring taking place in the Product Bottle Room, 

including smear surveys of product bottles and bird cages, as well as air monitoring for alpha. 

This is evidence that alpha contamination, including airborne contamination, was of concern to 

the HP staff for this area. Given the nature of routine work activities encountered in the Product 

Bottle Room, it is unlikely that workers in this area would also encounter FAP that are 

comingled with the enriched uranium. 

Finding 2 Response: The Product Bottle Room in CPP was where highly concentrated liquid 

uranyl nitrate solution product bottles were stored and then shipped to Oak Ridge to be further 

refined and manufactured into reactor fuel. This process was used until 1969, when the uranium 

was converted to a solid oxide. To maintain a safe geometry, the stainless steel product bottles 

were kept in containers that looked like “bird cages.” 

Due to the composition of the product material, tight radiological controls with an emphasis on 

alpha contamination detection were utilized. This is illustrated in Figures 5, 6, and 7, which list 

alpha contamination smear results from product “bird cages” in 1955 and 1956. Contamination 

levels on a smear above the minimum detectable amount of 10 cpm gross alpha for a one minute 

count time were acted on. Figure 7 provides an example of two “bird cages” requiring 

“decontamination.” In both cases, the recorded gross alpha contamination levels are extremely 

low even before the adjustment for background (5 cpm). It should also be noted that the detected 

beta activity was also elevated on some of the smears. These measurements were made with no 

consideration of radon-thoron daughter interferences which were present in CPP. 
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Figure 5: Page 1 of 2 of Alpha Contamination Surveys for Product Bird 

Cages (Bird Cages 1955, page 2)
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Figure 6: Page 2 of 2 of Alpha Contamination Surveys for Product Bird 

Cages (Bird Cages 1955, page 3)
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Figure 7: Alpha Contamination Surveys for Product Bird Cages in February 1956

(Product Bottles 1956, page 2)

On page twenty one of Draft Review of Internal Alpha Exposure Potential at CPP Prior to 1963, 

an example is provided of potential alpha air activity in the Final Product Room in September 

1954. The same example is provided in Figure 8 of this report. An initial alpha result appears to 

be 5E-11 μCi. The result unit is likely to have been μCi/cc, as astutely pointed out in the note 

associated with Figure 5 in the SC&A report. It should be pointed out that there was a recount 

performed 40 minutes later to allow for radon-thoron daughter interferences to decay away. The 

count result is provided. There is not a calculated value provided but the count result is roughly 

40% lower, and based on the count result, seemed to require no further action. The 1952 CPP 

Health Physics Manual reports a general permissible concentration of 3E-11 μCi/cc for alpha 

emitters, as seen in Figure 9. (CPP 1952) The recount value would correspond to an air 

concentration less than 3E-11 μCi/cc. 
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Figure 8: Air Sample Record for CPP Final Product Room September 3, 1954 (Air Sampling 1955, page 15)

Figure 9: CPP Health Physics Manual, April 1952 

(CPP 1952, page 49)

It is agreed that contamination survey and air sampling related to the activities associated with 

final product at CPP demonstrate that area health physicists were cognizant of the potential for 

alpha contamination. A long-time CPP health physicist, in a documented communication, 

recalled not remembering “air activity in the product packaging area of ICPP, which was to be 

expected because they were very careful not to lose any of the product during those operations.” 

(DCAS 2014b). DCAS has concluded there is no compelling data to indicate that internal 

exposure potential was even remotely likely. 

Finding 3: SC&A identified several area contamination survey maps from 1954, 1955, 1957, 

1960, and 1961 that indicate that alpha contamination may have been the primary radiological 

concern for certain locations at the time of the survey. In many cases, the survey is a general 

contamination survey that did not detect beta/gamma activity, but directed that the identified 

locations with alpha contamination be cleaned up. 

Finding 3 Response: As a fuel reprocessing facility which employed three cycles of solvent 

extraction, the radionuclide composition of the process stream changed from fuel dissolution 

through final product bottling and storage. For most of CPP, beta/gamma contamination 

monitoring for controlling internal exposure potential was utilized because the source term was 

well tagged with fission products. Examples are provided in Figures 10 and 11, which are 
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surveys of the Operating/Sample Corridors and South Access Corridor respectively. The 

contamination levels reported were assumed to be beta/gamma unless noted otherwise.

Figure 10: Beta-Gamma Contamination Survey of Overhead Survey in the CPP-601 Sample Corridor in 

May 1954 (Overhead Contamination 1954, page 3)
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Figure 11: Beta-Gamma Contamination Survey of CPP-601 South Access Corridor

(CPP 1960a, page 14)

This is in sharp contrast to the analytical laboratories, where surveys for alpha contamination 

were much more prevalent. The recognition that alpha-emitting radionuclides could be present 

without a fission product tag is demonstrated in the examples provided in Figures 12 and 13. 

Figure 3, which was previously presented, is also of particular interest on this topic, because it 

demonstrates that even in the X-Cell, a high activity analytical cell used for research, including 

large quantities of alpha-emitting radionuclides, there was a focus on alpha contamination 

monitoring. Remarkably, there is very little alpha activity measured. This was due to good 

radiological hygiene practices that were utilized at the time. In practice, this included good 

housekeeping, “papering” down work surfaces with frequent replacement, and a general 

intolerance for contamination by the CPP health physics staff. (DCAS 2015). It was the relaxing 

of permissible contamination levels that led to the future contamination control problems at CPP. 
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Figure 12: Contamination Survey of CPP Labs 212/216 (CPP 1961a, page 25) 
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Figure 13: Contamination Survey of X-Cell in December 1961. Note the beta/gamma contamination level 

recording in the lower left hand corner. (CPP 1961a, page 6)

Figure 14 provides an example of not only a contamination survey of an analytical laboratory, 

but also the identification of potential sources of contamination. In the survey, there are several 

items identified – namely “used syringe,” “used tissues,” and “gloves” (in two locations). There 

is also a directive to promptly discard of the items. As noted in Draft Review of Internal Alpha 

Exposure Potential at CPP Prior to 1963 in Figure 10, radiological surveys were marked with

areas shaded that required cleaning of the areas. Hoods and sinks were typically the locations 

with the highest contamination levels. These are good health physics practices in keeping 

contamination levels to a minimum. 
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Review of Internal Alpha Exposure Potential at 

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Figure 14: Contamination Survey of CPP Labs 204/207 in June 1961. Note the identification 

of potential sources of contamination on the survey. (CPP 1961a, page 6)

Figure 12 provided an example of a survey where the contamination survey did not reflect that 

any measurements were made for beta/gamma contamination. Whether beta/gamma activity was 
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not detected or if the survey was strictly at alpha survey is impossible to ascertain. However, it is 

clear from other surveys that beta/gamma contamination surveys were performed. Figures 15 and 

16 provide examples of alpha and beta/gamma contamination results being reported on the same 

radiological survey. 

Figure 15: Alpha and Beta-Gamma Contamination Survey of CPP Labs 204/207 

in December 1960. (CPP 1960a, page 2)
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Figure 16: Alpha and Beta-Gamma Contamination Survey of CPP Labs 212/216 in 

November 1961. (CPP 1961b, page 24)
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It should be noted that during some of the later data captures to the INL Records Center for the 

SEC-00219 petition evaluation, there was a concerted effort to focus on alpha contamination 

surveys to aid in determining the beginning of the then already-identified alpha contamination 

control problem at CPP. This is seen in some of the names of the documents captured during the 

last data capture (January 2015) in support of the 83.13 evaluation. (See Table 3). Most of the 

health physics surveys, which provided alpha survey results, were captured. There were also 

many beta/gamma surveys that were not captured. It was noted that the results of beta/gamma

surveys and alpha surveys were sometimes recorded separately. 

Table 3: Examples of CPP Health Physics Surveys in Early 1960s Captured in January 2015

SRDB Ref ID Title

CPP 1960a CPP Surveys with Alpha Results April - December 1960

CPP 1961a CPP Routine HP Surveys with Alpha Results January - June 1961

CPP 1961b CPP Routine HP Surveys with Alpha Results July - December 1961

CPP 1962c CPP Routine HP Surveys with Alpha Results January - February 1962

CPP 1962b CPP Routine HP Surveys with Alpha Results February - March 1962

CPP 1962a CPP Routine HP Surveys with Alpha Results March 1962

CPP 1962d CPP Routine HP Surveys with Alpha Results April 1962

As with the conclusion to Finding #1, DCAS has concluded that alpha contamination without 

fission products was only in certain locations at CPP, related to process stream sampling and 

analyses, which were known to CPP staff. Radiation and contamination surveys demonstrate that 

even low levels of alpha contamination were not tolerated and were cleaned up quickly. 

The internal exposure potential from the alpha contamination levels presented in SCA-TR-2017-

SEC008 would be very small. The largest alpha contamination level from the examples 

presented was 1,500 dpm/100 cm2

 in Figure 8, which was a close-up from Figure 7. The figure 

shows the alpha contamination detected on opening to a hood in Lab 216 in 1955, which appears 

to be fixed, as there is an additional note of “31 cpm alpha on smear.” Even if the 1,500 dpm is 

assumed to be transferrable, is uniformly distributed on the entire lip of the hood, and can be 

resuspended into the air, the quantity of activity available to be inhaled by the worker is less than 

1 dpm using the following assumptions: 

• Total surface area (hood lip) = 6 ft. by 1 ft. (5575 cm2)

• Total activity = 1,500 dpm/100 cm2 x 5575 cm2

• Resuspension factor = 1E-05

Because of the episodic nature of the alpha contamination, present for short periods of time, due 

to decontamination efforts and not allowing the conditions to become persistent, a chronic 
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exposure would be unlikely. It is important to remember that the class added to the SEC for CPP 

was due to increased alpha contamination levels, leading to increased internal exposure potential. 

There was not an increase in personnel monitoring, specifically bioassay, as the contamination 

levels increased. An ever-increasing accepting attitude of contamination and contamination 

problems at CPP eventually led to a facility Health Physics upgrade program. 

Dose reconstruction for INL workers accounts for actinides for both monitored and unmonitored 

workers. Even if a worker at CPP was not on a uranium bioassay program, the gross beta and 

gross gamma bioassay measurements for monitored workers have ratios of actinides assigned 

based on ratios to Sr-90 and Cs-137 (the gross beta and gross gamma indicator nuclides). These 

ratios are provided in Table 5-22 and Table 5-23 in ORAUT-TKBS-0007-5 Rev 3, Idaho 

National Laboratory and Argonne National Laboratory-West – Occupational Internal Dose. 

This is also true for whole body counts which were performed at INL, beginning in 1961. 

For unmonitored workers, a hypothetical missed internal dose approach is based on the 

assumption that the most likely type of bioassay measurement was performed on the last day of 

the calendar year and the result was one half the minimum detectable activity (MDA). The 

contribution from actinides is assumed for an unmonitored worker just like for a monitored 

worker. Again, this would be true for whole body counting as well. Thus, the current dose 

reconstruction methods account for potential small contributions from actinides. 

Finding 4: Based on a limited set of air samples in Room 216 from November of 1954, it is 

apparent that there was airborne alpha activity present. Evidence suggests the airborne alpha 

activity was uranium-233 (U-233), in the form of uranium oxide (U3O8). In two of the three 

examples, the airborne long-lived alpha activity bounded the airborne beta activity. 

Finding 4 Response: CPP-602 was a three story building which housed numerous laboratory 

facilities. Rooms 212 and 216 in CPP-602 were analytical laboratories dedicated to uranium 

process measurements to quantify uranium isotopes. (CPP 1977) The laboratories were 

connected, as seen in Figure 17. Sample preparations and mass spectrometry measurements 

were performed in the laboratories. A mass spectrometry method called Thermal Ionization Mass 

Spectrometry (TIMS) was utilized in these laboratories. The TIMS method requires a chemically 

purified sample and tracer to be plated onto a rhenium filament. The filament was then heated in 

a chamber connected to the mass spectrometer, causing ionization of the atoms, which were then 

introduced into the mass spectrometer and separated by the electromagnet, based on the mass to 

charge ratio. TIMS is a highly sensitive isotope mass characterization technique, making it an 

ideal method of uranium process measurements. 

CPP utilized uranium-233 (U-233) as the analytical tracer for TIMS. In a personnel interview 

with an analytical chemist that worked in the CPP laboratories, it was recalled that “the spike of 

U-233 was the dominant uranium isotope in the samples submitted for analysis (and in loose

contamination in the mass spec lab). Since the spike was added in the shift lab as an analytical

tracer, workers in other areas of the plant, outside the labs, were not exposed to U-233.” (DCAS

2014d) The chemist went on to state that while the lab was capable of analyzing nanogram
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samples of uranium, larger samples were often run, including samples of a “few micrograms 

with 1 microgram of U-233 added to each sample.” 

Given the large quantity of U-233 used in TIMS measurements and the need to plate the samples 

on a metal filament, it is not surprising that small contamination events occurred. However, the 

U-233 contamination tended to be small and was cleaned up quickly. Given the function of the

laboratories, contaminants could not be tolerated for long without affecting the accuracy of the

mass measurements. Figures 17, 18 and 19 provide a series of contamination surveys of Rooms

212 and 216 from September 2, 1960 through December 9, 1960, which demonstrate this.

Figure 17: CPP-602 Room 212 and 216 Contamination Survey, 

September 2, 1960 (CPP 1960, page 9) 
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Figure 18: CPP-602 Room 212 and 216 Contamination Survey, November 19, 1960

(CPP 1960, page 6)
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Figure 19: CPP-602 Room 212 and 216 Contamination Survey, December 9, 1960

(CPP 1960, page 4)
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Special bioassay for elevated levels of contamination due to U-233 were requested when deemed 

necessary by CPP Health Physics. A review of in-vitro bioassay collected at CPP in November 

1954, the time period of concern identified in the SC&A report, indicated there are thirteen 

special analyses for uranium. A review of the workers sampled indicates many were in the 

Chemistry department at CPP. (Hayden 1956) Uranium was not detected in any of the special 

bioassay samples. It should be noted that, in 1958, a U-233 specific urinalysis method was 

developed at INL. There were a small number of U-233 bioassay analyses in the late 1950s and 

early 1960s. All of these analyses were designated as “special” sample types, indicating that they 

were specific responses to U-233 contamination, which was only found in the CPP analytical 

laboratories. 

U-233 contamination in analytical laboratories that were involved in the preparation of process

samples for mass spectrometry measurements and the measurements themselves was known, and

even expected, given the large quantity of U-233 used as an analytical tracer is some

measurements. This is documented in alpha contamination surveys and in documented

communications with a former analytical chemist. When contamination from U-233 was found,

it was typically small in quantity and was cleaned up quickly. There are also documented cases

identified where CPP health physicists requested special bioassay due to U-233. All bioassay

results for U-233 were less than detection level. DCAS has concluded that U-233 internal

exposure potential is limited to a very small number of workers with bioassay monitoring

performed as deemed necessary.

Finding 5: SC&A identified a single example in which internal monitoring for uranium 

(specifically U-233) occurred out of the 32 reviewed claims who held job titles with the potential 

for laboratory work at CPP. Two samples were provided in the claimant’s monitoring record; 

however, a log of all medical treatment indicates that two additional follow-up samples 

occurred, which are missing from the dosimetry records supplied by the U.S. Department of 

Energy. One of the two follow-up samples was located via the NIOSH process known as “optical 

recognition imaging.” The disposition and availability of the other sample is unknown. 

Finding 5 Response: Claim1480 was reviewed for bioassay data included in the DOE Response 

File. The December 23, 1959 and December 31, 1959 urinalysis results for U-233 were found. 

As indicated on the Health Record in Figure 21 (page 42) of the Draft Review of Internal Alpha 

Exposure Potential at CPP Prior to 1963, there appear to have been two additional follow-up 

samples. The additional follow-up samples dated January 5, 1960 and January 11, 1960 were not 

found in this review, either. Of some interest is that that the December 23rd and December 31st

samples were collected by “Medical Services,” which, while not unusual at that time, may 

account for the possibility of results being in Medical records. Discussion with the lead dose 

reconstructor for INL indicated that occasionally indications of bioassay sampling are part of 

Medical records. He also indicated that the only bioassay data in those records are urine sample 

dates without the analytical results. This is exactly what SC&A discovered in Finding #5. The 

occupational medical records are now routinely being provided by INL in the DOE Response 

files for claimants. However, this has not always been the case. The medical records started 

being provided around claims numbered 20,000 and higher. The DOE Response File, which 
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includes medical records, has been re-requested for Claim [redacted]. DOE Request 

ADD_[redacted]_D132 was requested on March 6, 2018. 

RESPONSES TO SEPARATE OBSERVATIONS

Observation 1: Based on five identified interviews with former CPP workers having some 

knowledge of radiological operations, it is apparent that the HP staff were aware of, and took 

steps to control, alpha contamination in certain areas of the plant. These areas include the 

laboratories and other “product” areas. While the interviews indicate that an “incident”-based 

internal monitoring program was employed for alpha emitters, it is unclear what levels of alpha 

contamination would actually trigger “special bioassay” samples, versus more common 

decontamination activities. 

Observation 1 Response: CPP Health Physics staff members were expected to understand the 

operations processes in order to determine the source term of interest in various locations within 

CPP. Alpha contamination without fission products present were found at locations where the 

recovered uranium product was sampled, analyzed, and bottled. The administration of special 

bioassay was based on the professional judgment of the CPP health physicists. A review of the 

SRDB documents for CPP pre-1963 did not locate a document with prescriptive action levels for 

special bioassay. It should be kept in mind that the CPP Health Physics staff during the time 

period of interest included technicians that were Bachelor-level educated health physicists. 

Observation 2: Thirty-one of 32 claimants who worked at CPP prior to 1963 and had job types 

most likely to be associated with laboratory work did not have any internal monitoring results 

for uranium or other transuranic material (either special or routine). It cannot be inferred from 

available claimant files whether these workers should have been monitored and were not, were 

monitored and the records are unavailable, or did not experience any exposure potential to 

uranium warranting routine monitoring. 

Observation 2 Response: CPP analytical laboratory workers were placed on routine bioassay 

programs pre-1963. The CPP Body Fluid Sampling Schedule for 1956 provides a list of all CPP 

workers required by the CPP Health Physics manager to participate in routine bioassay to the 

Health Services Laboratory. The workers are listed by name and the requested analyses and 

frequencies are provided as well. It is evident from the document that the health physics staff 

considered the internal exposure potential for each worker before arriving at the requested 

bioassay program. There clearly were certain workers that were placed on uranium-specific 

bioassay due to internal exposure potential. 

Observation 3: During its review of claimants who may have worked in the laboratory areas of 

CPP, SC&A identified several non-claimants who appear to have been part of a regular routine 

monitoring program for uranium. This is logically indicative that a group of workers existed at 

CPP who had the potential for chronic (rather than episodic) exposure to uranium that was of 

radiological concern to the health and safety staff. 
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Page 33 of 36

This is a working document prepared by NIOSH’s Division of Compensation Analysis and Support (DCAS) or its contractor for use in discussions 

with the ABRWH or its Working Groups or Subcommittees. Draft, preliminary, interim, and White Paper documents are not final NIOSH or 

ABRWH (or their technical support and review contractors) positions unless specifically marked as such. This document represents preliminary 

positions taken on technical issues prepared by NIOSH or its contractor. NOTICE: This report has been reviewed to identify and redact any 

information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Observation 3 Response: The CPP Body Fluid Sampling Schedule for 1956 provides a listing 

of all CPP workers required to participate in routine bioassay programs. (Hayden 1956) As seen 

in Table 1 of this report, there was a small group of CPP workers (chemistry analysts and 

operations personnel) who were on a gross beta and uranium routine bioassay program. CPP 

Health Physics likely requested these analyses due to an elevated potential for uranium exposure, 

due to the nature of their tasks and locations. Some of these workers were on a semi-annual 

frequency, while others were on a quarterly frequency, again, due to internal exposure potential. 

Intakes of radioactive material, whether acute or chronic, that are identified via routine bioassay, 

are indications of failures in the protection of workers. Bioassay represents a final quality control 

check of workers for intakes of radioactive material. 

Observation 4: A documented 1958 incident involving airborne U-235 alpha activity in the ZCell indicates that HP was notified immediately and appropriate actions were taken, including 

air sampling, area swipe contamination surveys, and worker nasal swipes. Multiple bioassay 

samples were collected in the days immediately following the incident. Analysis of the available 

bioassay related to the incident indicates that exposures were likely minimal. This incident was 

also discussed in NIOSH 2015b. 

Observation 5: A documented incident in December 1958 describes a product line maintenance 

activity that resulted in a spill of U-235 in the access corridor of CPP. The activity involved an 

“HP Permit” and also had an HP presence in at least one of the two maintenance locations. 

Follow-up reports indicate HP and safety permits required more detail to avoid future incidents. 

Although not specified in the incident report, SC&A located at least one special uranium sample 

that was taken for a pipefitter involved in the spill. 

Observation 4 and 5 Response: The response to Observations #4 and #5 is combined, as both 

observations describe uranium contamination events with follow-up monitoring. Special 

bioassay, which is bioassay requested due to off-normal radiological conditions, was requested in 

both cases. Liquid spills, elevated airborne radioactivity, and facial contamination are examples 

of radiological indicators which would likely require some form of excreta measurement to 

determine 1) if an intake of radioactive material occurred and 2) if so, to aid in quantifying the 

intake and resultant radiative dose. The documentation of the December 1958 contamination 

event is consistent with the documented communication with a former CPP health physicist that 

significant events would have an INL incident report. (DCAS 2014b) 
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

Page 34 of 36

This is a working document prepared by NIOSH’s Division of Compensation Analysis and Support (DCAS) or its contractor for use in discussions 

with the ABRWH or its Working Groups or Subcommittees. Draft, preliminary, interim, and White Paper documents are not final NIOSH or 

ABRWH (or their technical support and review contractors) positions unless specifically marked as such. This document represents preliminary 

positions taken on technical issues prepared by NIOSH or its contractor. NOTICE: This report has been reviewed to identify and redact any 

information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

REFERENCES

Air Sampling, 1955, Air Sampling at CPP Including Alpha Sampling 1953–1955; Various Dates 

1953–1955; Idaho National Laboratory; SRDB Ref. ID: 153680 

Bird Cages, 1955, Alpha Contamination Survey of Bird Cages; May, 1955; Idaho National 

Laboratory; SRDB Ref. ID: 138134

CPP, 1952, CPP Health Physics Manual; April 1952; Idaho National Laboratory; SRDB Ref. 

ID: 8095 

CPP, 1957, Contamination Surveys Rooms 100-104, 108, 110, 112, 114, 116, 118, 200, 204, 207, 

208, 211-213, 215-217, 219, 221, 225-227, 229, 300, 301, 303-305, 307, 309, 311, 315, 319, 

321, LB-44, Operating Rooms, Engineering Offices, CPP Building 603 and 604 and Corridors; 

Idaho National Laboratory; SRDB Ref. ID: 138621 

CPP Surveys, 1960a, CPP Surveys with Alpha Results April – December 1960; Idaho National 

Laboratory; SRDB Ref. ID: 142015

CPP, 1960b, CPP Contamination Surveys with Alpha Results May – December 1960; Idaho 

National Laboratory; SRDB Ref. ID: 140408 

CPP, 1961a, Health Physics Floor Plans with Alpha Results July – December 1961; Idaho 

National Laboratory; SRDB Ref. ID: 140416 

CPP, 1961b, CPP Routine HP Surveys with Alpha Results July – December 1961; Idaho National 

Laboratory; SRDB Ref. ID: 142017

CPP, 1962a, CPP Routine HP Surveys with Alpha Results March 1962; Idaho National 

Laboratory; SRDB Ref. ID: 142020

CPP, 1962b, CPP Routine HP Surveys with Alpha Results February – March 1962; Idaho 

National Laboratory; SRDB Ref. ID: 142019 

CPP, 1962c, CPP Routine HP Surveys with Alpha Results January – February 1962; Idaho 

National Laboratory; SRDB Ref. ID: 142018 

CPP, 1962d, CPP Routine HP Surveys with Alpha Results April 1962; Idaho National 

Laboratory; SRDB Ref. ID: 142021

CPP, 1977, Idaho Chemical Processing Plant Safety Review Document, Section 4.10, Laboratory 

Facilities, Volume II, ACI-216-4.10; M. K. Valentine; Allied Chemical Corporation; April 1977; 

SRDB Ref ID: 142059
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

Page 35 of 36

This is a working document prepared by NIOSH’s Division of Compensation Analysis and Support (DCAS) or its contractor for use in discussions 

with the ABRWH or its Working Groups or Subcommittees. Draft, preliminary, interim, and White Paper documents are not final NIOSH or 

ABRWH (or their technical support and review contractors) positions unless specifically marked as such. This document represents preliminary 

positions taken on technical issues prepared by NIOSH or its contractor. NOTICE: This report has been reviewed to identify and redact any 

information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

DCAS (NIOSH Division of Compensation Analysis and Support), 2014a, In-person interview; 

documented communication with former Idaho National Laboratory worker [job title redacted] by 

DCAS, ORAU Team, and SC&A; Idaho Falls, Idaho; November 19, 2014; SRDB Ref ID: 142405 

DCAS (NIOSH Division of Compensation Analysis and Support), 2014b, In-person interview; 

documented communication with former Idaho National Laboratory worker [job title redacted] by 

DCAS and ORAU Team; Idaho Falls, Idaho; December 11, 2014; SRDB Ref ID: 141471 

DCAS (NIOSH Division of Compensation Analysis and Support), 2014c, In-person interview; 

documented communication with former Idaho National Laboratory worker [job title redacted] 

by DCAS, ORAU Team, ABRWH, and SC&A; Idaho Falls, Idaho; September 10, 2014; SRDB 

Ref. ID: 142398 

DCAS (NIOSH Division of Compensation Analysis and Support), 2014d, In-person interview; 

documented communication with former Idaho National Laboratory worker [job title redacted] 

by DCAS, ORAU Team, ABRWH, and SC&A; Idaho Falls, Idaho; November 17, 2014; SRDB 

Ref. ID: 159717 

DCAS (NIOSH Division of Compensation Analysis and Support), 2015, In-person interview; 

documented communication with former Idaho National Laboratory and Argonne National 

Laboratory – West worker [job title redacted] by DCAS and ORAU Team; Idaho Falls, Idaho; 

November 4, 2015; SRDB Ref ID: 150163 

DCAS (NIOSH Division of Compensation Analysis and Support), 2016, In-person interview; 

documented communication with former Idaho National Laboratory worker [job title redacted] by 

DCAS, ORAU Team, and SC&A; Idaho Falls, Idaho; November 8, 2016; SRDB Ref ID: 166587 

Hayden, 1956, CPP Body Fluid Sampling Schedule (Revision 3/6/56); HA-44-56A-M; R.E. 

Hayden; March 6, 1956; Idaho National Laboratory; SRDB Ref. ID: 141719 

McCaslin, 1963, Whole Body Counting Procedures Standard Practices Manual; 6.24.1; J. W. 

McCaslin; April 1, 1963; Idaho National Laboratory; SRDB Ref. ID: 132561 

NIOSH, 2017, SEC Petition Evaluation Report – Petition SEC-00219 – Idaho National 

Laboratory, Revision 2; National Institute for Occupational Safety and Health (NIOSH); 

February 22, 2017. SRDB Ref. ID: 166679 

Overhead Contamination, 1954, Overhead Contamination in the ICPP Sample Corridor; Idaho 

National Laboratory; SRDB Ref. ID: 138137 

Product Bottles, 1956, Health Physics Sample Records Sheet Radiation and Contamination of 

Product Bottles February 1956; Idaho National Laboratory; SRDB Ref. ID: 139204 
Response Paper Response to SCA-TR-2017-SEC008, “Draft 

Review of Internal Alpha Exposure Potential at 

CPP Prior to 1963” 

April 18, 2018

Page 36 of 36

This is a working document prepared by NIOSH’s Division of Compensation Analysis and Support (DCAS) or its contractor for use in discussions 

with the ABRWH or its Working Groups or Subcommittees. Draft, preliminary, interim, and White Paper documents are not final NIOSH or 

ABRWH (or their technical support and review contractors) positions unless specifically marked as such. This document represents preliminary 

positions taken on technical issues prepared by NIOSH or its contractor. NOTICE: This report has been reviewed to identify and redact any 

information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Stroschein, 1967, Health Physics Manual of NRTS Areas Operated by Idaho Nuclear 

Corporation; edited by H. W. Stroschein and P. H. Maeser; Issued: April 1967; SRDB Ref ID: 

1029